CTCSS/DCS/SELCALL Processor
FX828
Write Only Register Description
GENERAL RESET (Hex address $01)
The reset command has no data attached to it. It sets the device registers into the specific (all
powersaved) states as listed below:
REGISTER NAME
HEX
ADDRESS
$80
BIT 7
(D7)
0
BIT 6
(D6)
0
BIT 5
(D5)
0
BIT 4
(D4)
0
BIT 3
(D3)
0
BIT 2
(D2)
0
BIT 1
(D1)
0
BIT 0
D0)
0
SIGNALLING CONTROL
SELCALL & SUB-AUDIO STATUS
SIGNALLING SET-UP
$81
$82
0
0
0
0
0
0
0
0
X
0
X
0
X
0
X
0
CTCSS TX / FAST RX FREQUENCY (1)
CTCSS TX / FAST RX FREQUENCY (2)
$83
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
RX TONE PROGRAM
RX TONE PROGRAM
DCS BYTE 3
DCS BYTE 2
DCS BYTE 1
GENERAL CONTROL
AUDIO CONTROL
AUDIO CONTROL
GENERAL PURPOSE TIMER
SELCALL TX
(1)
(2)
$84
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
$85
$86
$87
$88
$8A
(1)
(2)
$8B
$8D
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
(1)
(2)
SELCALL TX
IRQ MASK
IRQ FLAG
$8E
$8F
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
X = undefined
SIGNALLING CONTROL Register (Hex address $80)
This register is used to control the functions of the device as described below:
Bit 7 should be set to “1” to enable the CTCSS/DCS subaudio transmitter. The
subaudio Tx type will depend on the state of the SUBAUDIO TX MODE (Bit 1
SIGNALLING SET-UP Register $82).
SUBAUDIO TX
ENABLE
(Bit 7)
Bit 6 should be set to “1” to enable the CTCSS/Selcall tone decoder or the DCS
decoder. Note: See also Bit 0 for DCS decoder operation.
TONE DECODER
ENABLE
(Bit 6)
Bits 7 and 6 should not both be set to “1” when Bit 0 is set to “1” because the
DCS function is half-duplex only.
When this bit is "1", the FAST CTCSS DETECT or FAST CTCSS PREDICTIVE
mode is enabled, depending upon the setting of FAST CTCSS MODE (Bit 3
SIGNALLING SET-UP Register, $82). When this bit is "0", both FAST CTCSS
DETECT and FAST CTCSS PREDICTIVE tone detectors are disabled.
CTCSS FAST
DETECT ENABLE
(Bit 5)
When this bit is "1" the Selcall transmitter is enabled. When this bit is "0" the
Selcall transmitter is disabled and powersaved.
SELCALL TX
ENABLE
(Bit 2)
When this bit is "1" and Bit 6 is “1”, the DCS decoder is enabled. When this bit
is "0" the DCS decoder is disabled.
DCS RX ENABLE
(Bit 0)
The DCS decoder and the subaudio (CTCSS or DCS) transmitter should not be
enabled at the same time.
Reserved for future use. These bits should be set to "0".
(Bits 4, 3, and 1)
© 2009 CML Microsystems Plc
10
D/828/4